


Mormor Advent Challenge 2020 Day 5: Snowballs

by RueRambunctious



Series: Mormor Advent Challenge 2020 [4]
Category: Sherlock (TV), Sherlock Holmes & Related Fandoms
Genre: M/M, Mermen, Snow, mermaid au
Language: English
Status: Completed
Published: 2020-12-09
Updated: 2020-12-09
Packaged: 2021-03-10 04:08:16
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,113
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27977853
Author URL: https://archiveofourown.org/users/RueRambunctious/pseuds/RueRambunctious
Summary: Sebastian is a deep sea merman. His companion Jim wants a trip to the surface.
Relationships: Sebastian Moran/Jim Moriarty
Series: Mormor Advent Challenge 2020 [4]
Series URL: https://archiveofourown.org/series/2044660
Comments: 2
Kudos: 10





	Mormor Advent Challenge 2020 Day 5: Snowballs

It was exceptionally bright at this time of year. The surface of the water would freeze, snow would lie atop it, and light would refract through that, filtering down into the depths.

The cold did not bother Sebastian Moran. He was proportionally built much like any other deep sea merperson on this part of the hemisphere: hulking, with enough insulating blubber and dense muscle not to mind the water’s winter chill. There were two remarkable things about his appearance. Firstly, Seb’s actual size – he was enormous, the deeper the water the bigger the lifeform, and merfolk as large as him rarely left their deep waters. This was partly because decompression sickness was a common malady for those who dared, and also because deepest sea merfolk weren’t a social lot. They didn’t have to be, when they could swallow up or squash most other life forms.

The second noticeable thing about Sebastian Moran’s appearance were his scars. He’d eaten and toyed with thousands of vessels over the years, and several had left their mark. When he was little more than a sproglet (and too reckless by half) Seb had almost skewered himself on the claws of an exotic figurehead, leaving parallel scars like mottled stretchmarks over his belly. When he’d been a foolhardy teen, he had tried to take out the entire East India Company and lost much of the flesh around his eye to cannonfire. Had he not been a saltwater-dwelling merman and already too big for most creatures to eat, he may not have survived.

Sebastian’s companion, meanwhile, survived for no logical reason beyond that nature was not without its cruelty or anomalies. Jim Moriarty seemed made up of bone, wit, and malice. His face was almost entirely teeth and sunken dark eyes the colour of Sebastian’s home waters. Jim’s skin was eigengrau flecked with white. He had no blubber to speak of and he was swifter than death.

Most fish had a level of magnetism that helped them navigate the sea, but Jim’s magnetism was beyond that of any other creature Seb had ever encountered. The merman (if that was what he truly was, as Sebastian had his doubts about the eerie fishbone splinter of a creature) could find treasure with an accuracy that seemed highly unnatural.

Still, Sebastian had visited the merfolk colonies of the Bermuda Triangle where the mermaids were said to be so magnetic as to send human ships and planes haywire, and there was a sliver of peculiarity in Jim which was akin to their’s. So perhaps Jim really was a merman.

The most striking thing about Jim Moriarty, if one was brave or foolish enough to linger long enough to get past the startlingly skeletal physique (like a shrimp! Not that Seb would dare mention that aloud) was Jim’s bioluminescence. Jim was drably coloured and well camouflaged most of the time, but sometimes, in rare, beautiful moments, something triggered a glow within Jim that Sebastian found most captivating. He found tiny Jim captivating in general, but when the alleged merman glowed… oh… He was a sight to behold at any depth.

However, at that very moment, Jim was aggrieved that Sebastian was not striking… anything at all.

“You _said_ you’d smash the ice,” the miniscule merman sniffed. “What good are you being so ridiculously enormous if you cannot even do that?”

Sebastian did not want to explain that he had lost all thought of breaking said ice for Jim in favour of simply looking at Jim. The overpowering magnetism was highly distracting, and highly confusing too, given their entirely mismatched sizes.

Sebastian grunted instead and swam the last small distance to the surface. Jim held tight as the bigger merman did so, because fast or not the tiny creature would take all day to get there on his own efforts.

Seb dragged his nails experimentally down the underside of the ice. He felt Jim’s interested gaze on him as he found a weak spot and punched upwards with considerable force.

“I said crack the ice for me, not obliterate it all,” Jim said dryly. The calm quiver of his gills suggested he was pleased despite his teasing tone.

Sebastian lifted Jim to the surface edge and watched with fascination as twilight shone right through Jim’s body. They kept away from brightest sunlight most days; their skin was not built to withstand it.

Jim squirmed onto the remaining ice with all of the grace of a baby seal, which Sebastian watched through reflections in the jagged ice, lest Jim notice the soft affection on his giant face.

Sebastian rose out of the water upto mid-chest. He rested his forearms experimentally on a glacial block, which groaned under the pressure but only cracked a little.

Sebastian looked around their dusky white surroundings, then back at Jim. Jim was wriggling through the snow with suppressed delight, his needle-thin teeth taking up even more of his face than normal.

“It’s rude to stare,” Jim scolded suddenly, squinting up at the enormous merman.

Sebastian rolled his eyes. “You know I can barely see on the surface, and you’re so slight and transparent if I look away too long I’ll lose you.”

A hum of wicked amusement juddered Jim’s tone. “How well can you see me?”

Seb moaned low in his gills in warning. “Whatever you’re thinking, don’t do it. I could squish y-”

Something sharp, small and cold hit Sebastian’s side. “What was that?”

Another peculiar nip caught his elbow, then his rib. “What are you doing, you accursed little creature?” Seb demanded, feeling more perplexed than annoyed. His companion was always manifesting abilities which normal, decent merfolk did not have.

He was fascinating that way.

Jim made a sound of mirth and Sebastian sunk lower in the water to see the miscreant better. “I believe these are called ‘snowballs’ by the humans,” Jim said glibly, and threw something white and round at Seb’s chin.

Sebastian arched a brow and tried to grasp a dusting of snow from the surrounding ice. He hovered it over Jim playfully. “Is it?” the large merman said flatly.

Jim squalled as snow fell from between Sebastian’s thick fingers (still pinched) above him. “Don’t you dare!”

Sebastian laughed fondly, ice cracking in the distance from the booming vibrations. “You started this!” 

Nonetheless, he moved his hand aside and dropped the snow into the water. “What else do humans do?”

“They watch the sun come up,” Jim said in an odd voice.

“If you stay in my shadow we could probably stay for a while before we get burned,” Sebastian mused.

Jim’s bioluminescence flickered, subconsciously mimicking the sky colours they would wait for. “Alright, Seb,” he said.


End file.
